Huge file created whlie dumping fs

To: misc_(_at_)_openbsd_(_dot_)_org

Subject: Huge file created whlie dumping fs

From: "Alex Kirk" <alex_(_at_)_schnarff_(_dot_)_com>

Date: Thu, 19 Sep 2002 14:47:00 GMT

I hate to have to come back to this list again when I've been asking so much
of its members the last few days, but I've got another issue that's
completely baffled me and could cause serious problems for my server.

After having spoken with people here about a crash I suffered while trying
to dump a filesystem from one drive to another while still connected to the
Internet, I tried the process again last night after newfs'ing the
destination to make sure it was clean and turning off my DSL modem:

cd /home; tar cvf - . | (cd /mnt/newhome; tar xpf - )

I didn't see how it ran, as I'm not on-site with the machine and I had a
friend who was run the command for me.

When I got up this morning to check on things, I saw that my /home partition
-- the source -- was at 105% capacity, while the /mnt/newhome partition
seemed to have everything in it. After a bit of searching, I found the
following file in both /home and /mnt/newhome:

-rw-r--r-- 1 root qmail 2595153920 Sep 18 23:39 _

Running "more" against it, the file spat out a combination of binary data
and what appeared to be the contents of all the files in /home, in the order
that tar would have come across them.

I admit to being a bit confused as to why this file would have been:

a) Created at all
b) Present in both the source and destination directories
c) Owned by root:qmail